B modeling
==============


Characteristics of B modeling
-------------------------------------

The second cut we are testing corresponds to the case where two of the edges of TETRA10 see the *lsn* cancel out exactly twice, at one of their ends and at their midpoint. An example of this configuration is shown in Figure.


.. image:: images/1000000000000323000002F581BF366BCAAAE1D4.jpg
    :width: 4.5346in
    :height: 4.2693in


.. _RefImage_1000000000000323000002F581BF366BCAAAE1D4.jpg:

**Figure** 3.1-a **: representation of the cut from modeling B**

For cutting, we come back to the more classical case represented in Figure, whose subtetrahedron cutting is detailed in [:ref:`R7.02.12 <R7.02.12>`].


.. image:: images/1000000000000188000001C8D66542F2CA71670A.jpg
    :width: 3.6874in
    :height: 4.311in


.. _RefImage_1000000000000188000001C8D66542F2CA71670A.jpg:

**Figure** 3.1-b **: :** **corresponding healthy configuration**


Characteristics of the mesh
----------------------------

To "find yourself" in this cutting configuration, the *lsn* is chosen spherical, with a center C (:math:`-\frac{1}{2}`, :math:`-\frac{1}{2}`, :math:`-1`) and with a radius :math:`R=\frac{\sqrt{(14)}}{2}`

The edges of the tetrahedron are then intersected by the *level set* at the following 6 points:


.. csv-table::

    "Intersection point", "Coordinates"
    "IP1 ", "(1,0,0)"
    "IP2 ", "(0,1,0)"
    "IP3 ", "(0.5,0.5,0)"
    "IP4 ", "(0.5,0,0.5)"
    "IP5 ", "(0,0,0.5)"
    "IP6 ", "(0,0, :math:`\sqrt{(3)}-1`)"



Tested sizes and results
------------------------------

After executing the command MODI_MODELE_XFEM, it is checked that the 6 intersection points IP1, IP2,, IP3,, IP4, IP5 and IP6 are in the group NFISSU and that their position is correct.


.. csv-table::

    "Quantities tested", "Reference type", "Reference value", "Tolerance"
    "COORX IP1 ", "'ANALYTIQUE'", "1.0", "10E-06"
    "COORY IP1 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP1 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORX IP2 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORY IP2 ", "'ANALYTIQUE'", "1.0", "10E-06"
    "COORZ IP2 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORX IP3 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORY IP3 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORZ IP3 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORX IP4 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORY IP4 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP4 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORX IP5 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORY IP5 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP5 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORX IP6 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORY IP6 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP6 ", "'ANALYTIQUE'", "0, 732050808", "10E-06"


The cut mesh (Figure) was also post-processed using SALOME. The cut obtained is in accordance with expectations, with 4 subtetrahedra that are consistent with the discontinuity.

.. image:: images/100002010000016D000001E1126F97154DBD859B.png
    :width: 4.2075in
    :height: 4.3827in


.. _RefImage_100002010000016D000001E1126F97154DBD859B.png:


.. image:: images/10000201000001940000018520FD2F00CE47C01E.png
    :width: 4.2075in
    :height: 4.0516in


.. _RefImage_10000201000001940000018520FD2F00CE47C01E.png:

**Figure** 3.3-a **: B** modeling cutting configuration**